freshlybakedca.ke
Git fork
1#define DISABLE_SIGN_COMPARE_WARNINGS
2
3#include "git-compat-util.h"
4#include "environment.h"
5#include "gettext.h"
6#include "hex.h"
7#include "odb.h"
8#include "commit.h"
9#include "diff.h"
10#include "revision.h"
11#include "progress.h"
12#include "pack.h"
13#include "pack-bitmap.h"
14#include "hash-lookup.h"
15#include "pack-objects.h"
16#include "path.h"
17#include "commit-reach.h"
18#include "prio-queue.h"
19#include "trace2.h"
20#include "tree.h"
21#include "tree-walk.h"
22#include "pseudo-merge.h"
23#include "oid-array.h"
24#include "config.h"
25#include "alloc.h"
26#include "refs.h"
27#include "strmap.h"
28#include "midx.h"
29#include "pack-revindex.h"
30
31struct bitmapped_commit {
32 struct commit *commit;
33 struct ewah_bitmap *bitmap;
34 struct ewah_bitmap *write_as;
35 int flags;
36 int xor_offset;
37 uint32_t commit_pos;
38 unsigned pseudo_merge : 1;
39};
40
41static inline int bitmap_writer_nr_selected_commits(struct bitmap_writer *writer)
42{
43 return writer->selected_nr - writer->pseudo_merges_nr;
44}
45
46void bitmap_writer_init(struct bitmap_writer *writer, struct repository *r,
47 struct packing_data *pdata,
48 struct multi_pack_index *midx)
49{
50 memset(writer, 0, sizeof(struct bitmap_writer));
51 if (writer->bitmaps)
52 BUG("bitmap writer already initialized");
53 writer->repo = r;
54 writer->bitmaps = kh_init_oid_map();
55 writer->pseudo_merge_commits = kh_init_oid_map();
56 writer->to_pack = pdata;
57 writer->midx = midx;
58
59 string_list_init_dup(&writer->pseudo_merge_groups);
60
61 load_pseudo_merges_from_config(r, &writer->pseudo_merge_groups);
62}
63
64static void free_pseudo_merge_commit_idx(struct pseudo_merge_commit_idx *idx)
65{
66 if (!idx)
67 return;
68 free(idx->pseudo_merge);
69 free(idx);
70}
71
72static void pseudo_merge_group_release_cb(void *payload, const char *name UNUSED)
73{
74 pseudo_merge_group_release(payload);
75 free(payload);
76}
77
78void bitmap_writer_free(struct bitmap_writer *writer)
79{
80 uint32_t i;
81 struct pseudo_merge_commit_idx *idx;
82
83 if (!writer)
84 return;
85
86 ewah_free(writer->commits);
87 ewah_free(writer->trees);
88 ewah_free(writer->blobs);
89 ewah_free(writer->tags);
90
91 kh_destroy_oid_map(writer->bitmaps);
92
93 kh_foreach_value(writer->pseudo_merge_commits, idx,
94 free_pseudo_merge_commit_idx(idx));
95 kh_destroy_oid_map(writer->pseudo_merge_commits);
96 string_list_clear_func(&writer->pseudo_merge_groups,
97 pseudo_merge_group_release_cb);
98
99 for (i = 0; i < writer->selected_nr; i++) {
100 struct bitmapped_commit *bc = &writer->selected[i];
101 if (bc->write_as != bc->bitmap)
102 ewah_free(bc->write_as);
103 ewah_free(bc->bitmap);
104 }
105 free(writer->selected);
106}
107
108void bitmap_writer_show_progress(struct bitmap_writer *writer, int show)
109{
110 writer->show_progress = show;
111}
112
113/**
114 * Build the initial type index for the packfile or multi-pack-index
115 */
116void bitmap_writer_build_type_index(struct bitmap_writer *writer,
117 struct pack_idx_entry **index)
118{
119 uint32_t i;
120 uint32_t base_objects = 0;
121
122 if (writer->midx)
123 base_objects = writer->midx->num_objects +
124 writer->midx->num_objects_in_base;
125
126 writer->commits = ewah_new();
127 writer->trees = ewah_new();
128 writer->blobs = ewah_new();
129 writer->tags = ewah_new();
130 ALLOC_ARRAY(writer->to_pack->in_pack_pos, writer->to_pack->nr_objects);
131
132 for (i = 0; i < writer->to_pack->nr_objects; ++i) {
133 struct object_entry *entry = (struct object_entry *)index[i];
134 enum object_type real_type;
135
136 oe_set_in_pack_pos(writer->to_pack, entry, i);
137
138 switch (oe_type(entry)) {
139 case OBJ_COMMIT:
140 case OBJ_TREE:
141 case OBJ_BLOB:
142 case OBJ_TAG:
143 real_type = oe_type(entry);
144 break;
145
146 default:
147 real_type = odb_read_object_info(writer->to_pack->repo->objects,
148 &entry->idx.oid, NULL);
149 break;
150 }
151
152 switch (real_type) {
153 case OBJ_COMMIT:
154 ewah_set(writer->commits, i + base_objects);
155 break;
156
157 case OBJ_TREE:
158 ewah_set(writer->trees, i + base_objects);
159 break;
160
161 case OBJ_BLOB:
162 ewah_set(writer->blobs, i + base_objects);
163 break;
164
165 case OBJ_TAG:
166 ewah_set(writer->tags, i + base_objects);
167 break;
168
169 default:
170 die("Missing type information for %s (%d/%d)",
171 oid_to_hex(&entry->idx.oid), real_type,
172 oe_type(entry));
173 }
174 }
175}
176
177int bitmap_writer_has_bitmapped_object_id(struct bitmap_writer *writer,
178 const struct object_id *oid)
179{
180 return kh_get_oid_map(writer->bitmaps, *oid) != kh_end(writer->bitmaps);
181}
182
183/**
184 * Compute the actual bitmaps
185 */
186
187void bitmap_writer_push_commit(struct bitmap_writer *writer,
188 struct commit *commit, unsigned pseudo_merge)
189{
190 if (writer->selected_nr >= writer->selected_alloc) {
191 writer->selected_alloc = (writer->selected_alloc + 32) * 2;
192 REALLOC_ARRAY(writer->selected, writer->selected_alloc);
193 }
194
195 if (!pseudo_merge) {
196 int hash_ret;
197 khiter_t hash_pos = kh_put_oid_map(writer->bitmaps,
198 commit->object.oid,
199 &hash_ret);
200
201 if (!hash_ret)
202 die(_("duplicate entry when writing bitmap index: %s"),
203 oid_to_hex(&commit->object.oid));
204 kh_value(writer->bitmaps, hash_pos) = NULL;
205 }
206
207 writer->selected[writer->selected_nr].commit = commit;
208 writer->selected[writer->selected_nr].bitmap = NULL;
209 writer->selected[writer->selected_nr].write_as = NULL;
210 writer->selected[writer->selected_nr].flags = 0;
211 writer->selected[writer->selected_nr].pseudo_merge = pseudo_merge;
212
213 writer->selected_nr++;
214}
215
216static uint32_t find_object_pos(struct bitmap_writer *writer,
217 const struct object_id *oid, int *found)
218{
219 struct object_entry *entry;
220
221 entry = packlist_find(writer->to_pack, oid);
222 if (entry) {
223 uint32_t base_objects = 0;
224 if (writer->midx)
225 base_objects = writer->midx->num_objects +
226 writer->midx->num_objects_in_base;
227
228 if (found)
229 *found = 1;
230 return oe_in_pack_pos(writer->to_pack, entry) + base_objects;
231 } else if (writer->midx) {
232 uint32_t at, pos;
233
234 if (!bsearch_midx(oid, writer->midx, &at))
235 goto missing;
236 if (midx_to_pack_pos(writer->midx, at, &pos) < 0)
237 goto missing;
238
239 if (found)
240 *found = 1;
241 return pos;
242 }
243
244missing:
245 if (found)
246 *found = 0;
247 warning("Failed to write bitmap index. Packfile doesn't have full closure "
248 "(object %s is missing)", oid_to_hex(oid));
249 return 0;
250}
251
252static void compute_xor_offsets(struct bitmap_writer *writer)
253{
254 static const int MAX_XOR_OFFSET_SEARCH = 10;
255
256 int i, next = 0;
257
258 while (next < writer->selected_nr) {
259 struct bitmapped_commit *stored = &writer->selected[next];
260 int best_offset = 0;
261 struct ewah_bitmap *best_bitmap = stored->bitmap;
262 struct ewah_bitmap *test_xor;
263
264 if (stored->pseudo_merge)
265 goto next;
266
267 for (i = 1; i <= MAX_XOR_OFFSET_SEARCH; ++i) {
268 int curr = next - i;
269
270 if (curr < 0)
271 break;
272 if (writer->selected[curr].pseudo_merge)
273 continue;
274
275 test_xor = ewah_pool_new();
276 ewah_xor(writer->selected[curr].bitmap, stored->bitmap, test_xor);
277
278 if (test_xor->buffer_size < best_bitmap->buffer_size) {
279 if (best_bitmap != stored->bitmap)
280 ewah_pool_free(best_bitmap);
281
282 best_bitmap = test_xor;
283 best_offset = i;
284 } else {
285 ewah_pool_free(test_xor);
286 }
287 }
288
289next:
290 stored->xor_offset = best_offset;
291 stored->write_as = best_bitmap;
292
293 next++;
294 }
295}
296
297struct bb_commit {
298 struct commit_list *reverse_edges;
299 struct bitmap *commit_mask;
300 struct bitmap *bitmap;
301 unsigned selected:1,
302 maximal:1,
303 pseudo_merge:1;
304 unsigned idx; /* within selected array */
305};
306
307static void clear_bb_commit(struct bb_commit *commit)
308{
309 free_commit_list(commit->reverse_edges);
310 bitmap_free(commit->commit_mask);
311 bitmap_free(commit->bitmap);
312}
313
314define_commit_slab(bb_data, struct bb_commit);
315
316struct bitmap_builder {
317 struct bb_data data;
318 struct commit **commits;
319 size_t commits_nr, commits_alloc;
320};
321
322static void bitmap_builder_init(struct bitmap_builder *bb,
323 struct bitmap_writer *writer,
324 struct bitmap_index *old_bitmap)
325{
326 struct rev_info revs;
327 struct commit *commit;
328 struct commit_list *reusable = NULL;
329 struct commit_list *r;
330 unsigned int i, num_maximal = 0;
331
332 memset(bb, 0, sizeof(*bb));
333 init_bb_data(&bb->data);
334
335 reset_revision_walk();
336 repo_init_revisions(writer->to_pack->repo, &revs, NULL);
337 revs.topo_order = 1;
338 revs.first_parent_only = 1;
339
340 for (i = 0; i < writer->selected_nr; i++) {
341 struct bitmapped_commit *bc = &writer->selected[i];
342 struct bb_commit *ent = bb_data_at(&bb->data, bc->commit);
343
344 ent->selected = 1;
345 ent->maximal = 1;
346 ent->pseudo_merge = bc->pseudo_merge;
347 ent->idx = i;
348
349 ent->commit_mask = bitmap_new();
350 bitmap_set(ent->commit_mask, i);
351
352 add_pending_object(&revs, &bc->commit->object, "");
353 }
354
355 if (prepare_revision_walk(&revs))
356 die("revision walk setup failed");
357
358 while ((commit = get_revision(&revs))) {
359 struct commit_list *p = commit->parents;
360 struct bb_commit *c_ent;
361
362 parse_commit_or_die(commit);
363
364 c_ent = bb_data_at(&bb->data, commit);
365
366 /*
367 * If there is no commit_mask, there is no reason to iterate
368 * over this commit; it is not selected (if it were, it would
369 * not have a blank commit mask) and all its children have
370 * existing bitmaps (see the comment starting with "This commit
371 * has an existing bitmap" below), so it does not contribute
372 * anything to the final bitmap file or its descendants.
373 */
374 if (!c_ent->commit_mask)
375 continue;
376
377 if (old_bitmap && bitmap_for_commit(old_bitmap, commit)) {
378 /*
379 * This commit has an existing bitmap, so we can
380 * get its bits immediately without an object
381 * walk. That is, it is reusable as-is and there is no
382 * need to continue walking beyond it.
383 *
384 * Mark it as such and add it to bb->commits separately
385 * to avoid allocating a position in the commit mask.
386 */
387 commit_list_insert(commit, &reusable);
388 goto next;
389 }
390
391 if (c_ent->maximal) {
392 num_maximal++;
393 ALLOC_GROW(bb->commits, bb->commits_nr + 1, bb->commits_alloc);
394 bb->commits[bb->commits_nr++] = commit;
395 }
396
397 if (p) {
398 struct bb_commit *p_ent = bb_data_at(&bb->data, p->item);
399 int c_not_p, p_not_c;
400
401 if (!p_ent->commit_mask) {
402 p_ent->commit_mask = bitmap_new();
403 c_not_p = 1;
404 p_not_c = 0;
405 } else {
406 c_not_p = bitmap_is_subset(c_ent->commit_mask, p_ent->commit_mask);
407 p_not_c = bitmap_is_subset(p_ent->commit_mask, c_ent->commit_mask);
408 }
409
410 if (!c_not_p)
411 continue;
412
413 bitmap_or(p_ent->commit_mask, c_ent->commit_mask);
414
415 if (p_not_c)
416 p_ent->maximal = 1;
417 else {
418 p_ent->maximal = 0;
419 free_commit_list(p_ent->reverse_edges);
420 p_ent->reverse_edges = NULL;
421 }
422
423 if (c_ent->maximal) {
424 commit_list_insert(commit, &p_ent->reverse_edges);
425 } else {
426 struct commit_list *cc = c_ent->reverse_edges;
427
428 for (; cc; cc = cc->next) {
429 if (!commit_list_contains(cc->item, p_ent->reverse_edges))
430 commit_list_insert(cc->item, &p_ent->reverse_edges);
431 }
432 }
433 }
434
435next:
436 bitmap_free(c_ent->commit_mask);
437 c_ent->commit_mask = NULL;
438 }
439
440 for (r = reusable; r; r = r->next) {
441 ALLOC_GROW(bb->commits, bb->commits_nr + 1, bb->commits_alloc);
442 bb->commits[bb->commits_nr++] = r->item;
443 }
444
445 trace2_data_intmax("pack-bitmap-write", writer->repo,
446 "num_selected_commits", writer->selected_nr);
447 trace2_data_intmax("pack-bitmap-write", writer->repo,
448 "num_maximal_commits", num_maximal);
449
450 release_revisions(&revs);
451 free_commit_list(reusable);
452}
453
454static void bitmap_builder_clear(struct bitmap_builder *bb)
455{
456 deep_clear_bb_data(&bb->data, clear_bb_commit);
457 free(bb->commits);
458 bb->commits_nr = bb->commits_alloc = 0;
459}
460
461static int fill_bitmap_tree(struct bitmap_writer *writer,
462 struct bitmap *bitmap,
463 struct tree *tree)
464{
465 int found;
466 uint32_t pos;
467 struct tree_desc desc;
468 struct name_entry entry;
469
470 /*
471 * If our bit is already set, then there is nothing to do. Both this
472 * tree and all of its children will be set.
473 */
474 pos = find_object_pos(writer, &tree->object.oid, &found);
475 if (!found)
476 return -1;
477 if (bitmap_get(bitmap, pos))
478 return 0;
479 bitmap_set(bitmap, pos);
480
481 if (parse_tree(tree) < 0)
482 die("unable to load tree object %s",
483 oid_to_hex(&tree->object.oid));
484 init_tree_desc(&desc, &tree->object.oid, tree->buffer, tree->size);
485
486 while (tree_entry(&desc, &entry)) {
487 switch (object_type(entry.mode)) {
488 case OBJ_TREE:
489 if (fill_bitmap_tree(writer, bitmap,
490 lookup_tree(writer->repo, &entry.oid)) < 0)
491 return -1;
492 break;
493 case OBJ_BLOB:
494 pos = find_object_pos(writer, &entry.oid, &found);
495 if (!found)
496 return -1;
497 bitmap_set(bitmap, pos);
498 break;
499 default:
500 /* Gitlink, etc; not reachable */
501 break;
502 }
503 }
504
505 free_tree_buffer(tree);
506 return 0;
507}
508
509static int reused_bitmaps_nr;
510static int reused_pseudo_merge_bitmaps_nr;
511
512static int fill_bitmap_commit(struct bitmap_writer *writer,
513 struct bb_commit *ent,
514 struct commit *commit,
515 struct prio_queue *queue,
516 struct prio_queue *tree_queue,
517 struct bitmap_index *old_bitmap,
518 const uint32_t *mapping)
519{
520 int found;
521 uint32_t pos;
522 if (!ent->bitmap)
523 ent->bitmap = bitmap_new();
524
525 prio_queue_put(queue, commit);
526
527 while (queue->nr) {
528 struct commit_list *p;
529 struct commit *c = prio_queue_get(queue);
530
531 if (old_bitmap && mapping) {
532 struct ewah_bitmap *old;
533 struct bitmap *remapped = bitmap_new();
534
535 if (commit->object.flags & BITMAP_PSEUDO_MERGE)
536 old = pseudo_merge_bitmap_for_commit(old_bitmap, c);
537 else
538 old = bitmap_for_commit(old_bitmap, c);
539 /*
540 * If this commit has an old bitmap, then translate that
541 * bitmap and add its bits to this one. No need to walk
542 * parents or the tree for this commit.
543 */
544 if (old && !rebuild_bitmap(mapping, old, remapped)) {
545 bitmap_or(ent->bitmap, remapped);
546 bitmap_free(remapped);
547 if (commit->object.flags & BITMAP_PSEUDO_MERGE)
548 reused_pseudo_merge_bitmaps_nr++;
549 else
550 reused_bitmaps_nr++;
551 continue;
552 }
553 bitmap_free(remapped);
554 }
555
556 /*
557 * Mark ourselves and queue our tree. The commit
558 * walk ensures we cover all parents.
559 */
560 if (!(c->object.flags & BITMAP_PSEUDO_MERGE)) {
561 pos = find_object_pos(writer, &c->object.oid, &found);
562 if (!found)
563 return -1;
564 bitmap_set(ent->bitmap, pos);
565 prio_queue_put(tree_queue,
566 repo_get_commit_tree(writer->repo, c));
567 }
568
569 for (p = c->parents; p; p = p->next) {
570 pos = find_object_pos(writer, &p->item->object.oid,
571 &found);
572 if (!found)
573 return -1;
574 if (!bitmap_get(ent->bitmap, pos)) {
575 bitmap_set(ent->bitmap, pos);
576 prio_queue_put(queue, p->item);
577 }
578 }
579 }
580
581 while (tree_queue->nr) {
582 if (fill_bitmap_tree(writer, ent->bitmap,
583 prio_queue_get(tree_queue)) < 0)
584 return -1;
585 }
586 return 0;
587}
588
589static void store_selected(struct bitmap_writer *writer,
590 struct bb_commit *ent, struct commit *commit)
591{
592 struct bitmapped_commit *stored = &writer->selected[ent->idx];
593 khiter_t hash_pos;
594
595 stored->bitmap = bitmap_to_ewah(ent->bitmap);
596
597 if (ent->pseudo_merge)
598 return;
599
600 hash_pos = kh_get_oid_map(writer->bitmaps, commit->object.oid);
601 if (hash_pos == kh_end(writer->bitmaps))
602 die(_("attempted to store non-selected commit: '%s'"),
603 oid_to_hex(&commit->object.oid));
604
605 kh_value(writer->bitmaps, hash_pos) = stored;
606}
607
608int bitmap_writer_build(struct bitmap_writer *writer)
609{
610 struct bitmap_builder bb;
611 size_t i;
612 int nr_stored = 0; /* for progress */
613 struct prio_queue queue = { compare_commits_by_gen_then_commit_date };
614 struct prio_queue tree_queue = { NULL };
615 struct bitmap_index *old_bitmap;
616 uint32_t *mapping = NULL;
617 int closed = 1; /* until proven otherwise */
618
619 if (writer->show_progress)
620 writer->progress = start_progress(writer->repo,
621 "Building bitmaps",
622 writer->selected_nr);
623 trace2_region_enter("pack-bitmap-write", "building_bitmaps_total",
624 writer->repo);
625
626 old_bitmap = prepare_bitmap_git(writer->to_pack->repo);
627 if (old_bitmap)
628 mapping = create_bitmap_mapping(old_bitmap, writer->to_pack);
629 else
630 mapping = NULL;
631
632 bitmap_builder_init(&bb, writer, old_bitmap);
633 for (i = bb.commits_nr; i > 0; i--) {
634 struct commit *commit = bb.commits[i-1];
635 struct bb_commit *ent = bb_data_at(&bb.data, commit);
636 struct commit *child;
637 int reused = 0;
638
639 if (fill_bitmap_commit(writer, ent, commit, &queue, &tree_queue,
640 old_bitmap, mapping) < 0) {
641 closed = 0;
642 break;
643 }
644
645 if (ent->selected) {
646 store_selected(writer, ent, commit);
647 nr_stored++;
648 display_progress(writer->progress, nr_stored);
649 }
650
651 while ((child = pop_commit(&ent->reverse_edges))) {
652 struct bb_commit *child_ent =
653 bb_data_at(&bb.data, child);
654
655 if (child_ent->bitmap)
656 bitmap_or(child_ent->bitmap, ent->bitmap);
657 else if (reused)
658 child_ent->bitmap = bitmap_dup(ent->bitmap);
659 else {
660 child_ent->bitmap = ent->bitmap;
661 reused = 1;
662 }
663 }
664 if (!reused)
665 bitmap_free(ent->bitmap);
666 ent->bitmap = NULL;
667 }
668 clear_prio_queue(&queue);
669 clear_prio_queue(&tree_queue);
670 bitmap_builder_clear(&bb);
671 free_bitmap_index(old_bitmap);
672 free(mapping);
673
674 trace2_region_leave("pack-bitmap-write", "building_bitmaps_total",
675 writer->repo);
676 trace2_data_intmax("pack-bitmap-write", writer->repo,
677 "building_bitmaps_reused", reused_bitmaps_nr);
678 trace2_data_intmax("pack-bitmap-write", writer->repo,
679 "building_bitmaps_pseudo_merge_reused",
680 reused_pseudo_merge_bitmaps_nr);
681
682 stop_progress(&writer->progress);
683
684 if (closed)
685 compute_xor_offsets(writer);
686 return closed ? 0 : -1;
687}
688
689/**
690 * Select the commits that will be bitmapped
691 */
692static inline unsigned int next_commit_index(unsigned int idx)
693{
694 static const unsigned int MIN_COMMITS = 100;
695 static const unsigned int MAX_COMMITS = 5000;
696
697 static const unsigned int MUST_REGION = 100;
698 static const unsigned int MIN_REGION = 20000;
699
700 unsigned int offset, next;
701
702 if (idx <= MUST_REGION)
703 return 0;
704
705 if (idx <= MIN_REGION) {
706 offset = idx - MUST_REGION;
707 return (offset < MIN_COMMITS) ? offset : MIN_COMMITS;
708 }
709
710 offset = idx - MIN_REGION;
711 next = (offset < MAX_COMMITS) ? offset : MAX_COMMITS;
712
713 return (next > MIN_COMMITS) ? next : MIN_COMMITS;
714}
715
716static int date_compare(const void *_a, const void *_b)
717{
718 struct commit *a = *(struct commit **)_a;
719 struct commit *b = *(struct commit **)_b;
720 return (long)b->date - (long)a->date;
721}
722
723void bitmap_writer_select_commits(struct bitmap_writer *writer,
724 struct commit **indexed_commits,
725 unsigned int indexed_commits_nr)
726{
727 unsigned int i = 0, j, next;
728
729 QSORT(indexed_commits, indexed_commits_nr, date_compare);
730
731 if (indexed_commits_nr < 100) {
732 for (i = 0; i < indexed_commits_nr; ++i)
733 bitmap_writer_push_commit(writer, indexed_commits[i], 0);
734
735 select_pseudo_merges(writer);
736
737 return;
738 }
739
740 if (writer->show_progress)
741 writer->progress = start_progress(writer->repo,
742 "Selecting bitmap commits", 0);
743
744 for (;;) {
745 struct commit *chosen = NULL;
746
747 next = next_commit_index(i);
748
749 if (i + next >= indexed_commits_nr)
750 break;
751
752 if (next == 0) {
753 chosen = indexed_commits[i];
754 } else {
755 chosen = indexed_commits[i + next];
756
757 for (j = 0; j <= next; ++j) {
758 struct commit *cm = indexed_commits[i + j];
759
760 if ((cm->object.flags & NEEDS_BITMAP) != 0) {
761 chosen = cm;
762 break;
763 }
764
765 if (cm->parents && cm->parents->next)
766 chosen = cm;
767 }
768 }
769
770 bitmap_writer_push_commit(writer, chosen, 0);
771
772 i += next + 1;
773 display_progress(writer->progress, i);
774 }
775
776 stop_progress(&writer->progress);
777
778 select_pseudo_merges(writer);
779}
780
781
782static int hashwrite_ewah_helper(void *f, const void *buf, size_t len)
783{
784 /* hashwrite will die on error */
785 hashwrite(f, buf, len);
786 return len;
787}
788
789/**
790 * Write the bitmap index to disk
791 */
792static inline void dump_bitmap(struct hashfile *f, struct ewah_bitmap *bitmap)
793{
794 if (ewah_serialize_to(bitmap, hashwrite_ewah_helper, f) < 0)
795 die("Failed to write bitmap index");
796}
797
798static const struct object_id *oid_access(size_t pos, const void *table)
799{
800 const struct pack_idx_entry * const *index = table;
801 return &index[pos]->oid;
802}
803
804static void write_selected_commits_v1(struct bitmap_writer *writer,
805 struct hashfile *f, off_t *offsets)
806{
807 int i;
808
809 for (i = 0; i < bitmap_writer_nr_selected_commits(writer); ++i) {
810 struct bitmapped_commit *stored = &writer->selected[i];
811 if (stored->pseudo_merge)
812 BUG("unexpected pseudo-merge among selected: %s",
813 oid_to_hex(&stored->commit->object.oid));
814
815 if (offsets)
816 offsets[i] = hashfile_total(f);
817
818 hashwrite_be32(f, stored->commit_pos);
819 hashwrite_u8(f, stored->xor_offset);
820 hashwrite_u8(f, stored->flags);
821
822 dump_bitmap(f, stored->write_as);
823 }
824}
825
826static void write_pseudo_merges(struct bitmap_writer *writer,
827 struct hashfile *f)
828{
829 struct oid_array commits = OID_ARRAY_INIT;
830 struct bitmap **commits_bitmap = NULL;
831 off_t *pseudo_merge_ofs = NULL;
832 off_t start, table_start, next_ext;
833
834 uint32_t base = bitmap_writer_nr_selected_commits(writer);
835 size_t i, j = 0;
836
837 CALLOC_ARRAY(commits_bitmap, writer->pseudo_merges_nr);
838 CALLOC_ARRAY(pseudo_merge_ofs, writer->pseudo_merges_nr);
839
840 for (i = 0; i < writer->pseudo_merges_nr; i++) {
841 struct bitmapped_commit *merge = &writer->selected[base + i];
842 struct commit_list *p;
843
844 if (!merge->pseudo_merge)
845 BUG("found non-pseudo merge commit at %"PRIuMAX, (uintmax_t)i);
846
847 commits_bitmap[i] = bitmap_new();
848
849 for (p = merge->commit->parents; p; p = p->next)
850 bitmap_set(commits_bitmap[i],
851 find_object_pos(writer, &p->item->object.oid,
852 NULL));
853 }
854
855 start = hashfile_total(f);
856
857 for (i = 0; i < writer->pseudo_merges_nr; i++) {
858 struct ewah_bitmap *commits_ewah = bitmap_to_ewah(commits_bitmap[i]);
859
860 pseudo_merge_ofs[i] = hashfile_total(f);
861
862 dump_bitmap(f, commits_ewah);
863 dump_bitmap(f, writer->selected[base+i].write_as);
864
865 ewah_free(commits_ewah);
866 }
867
868 next_ext = st_add(hashfile_total(f),
869 st_mult(kh_size(writer->pseudo_merge_commits),
870 sizeof(uint64_t)));
871
872 table_start = hashfile_total(f);
873
874 commits.alloc = kh_size(writer->pseudo_merge_commits);
875 CALLOC_ARRAY(commits.oid, commits.alloc);
876
877 for (i = kh_begin(writer->pseudo_merge_commits); i != kh_end(writer->pseudo_merge_commits); i++) {
878 if (!kh_exist(writer->pseudo_merge_commits, i))
879 continue;
880 oid_array_append(&commits, &kh_key(writer->pseudo_merge_commits, i));
881 }
882
883 oid_array_sort(&commits);
884
885 /* write lookup table (non-extended) */
886 for (i = 0; i < commits.nr; i++) {
887 int hash_pos;
888 struct pseudo_merge_commit_idx *c;
889
890 hash_pos = kh_get_oid_map(writer->pseudo_merge_commits,
891 commits.oid[i]);
892 if (hash_pos == kh_end(writer->pseudo_merge_commits))
893 BUG("could not find pseudo-merge commit %s",
894 oid_to_hex(&commits.oid[i]));
895
896 c = kh_value(writer->pseudo_merge_commits, hash_pos);
897
898 hashwrite_be32(f, find_object_pos(writer, &commits.oid[i],
899 NULL));
900 if (c->nr == 1)
901 hashwrite_be64(f, pseudo_merge_ofs[c->pseudo_merge[0]]);
902 else if (c->nr > 1) {
903 if (next_ext & ((uint64_t)1<<63))
904 die(_("too many pseudo-merges"));
905 hashwrite_be64(f, next_ext | ((uint64_t)1<<63));
906 next_ext = st_add3(next_ext,
907 sizeof(uint32_t),
908 st_mult(c->nr, sizeof(uint64_t)));
909 } else
910 BUG("expected commit '%s' to have at least one "
911 "pseudo-merge", oid_to_hex(&commits.oid[i]));
912 }
913
914 /* write lookup table (extended) */
915 for (i = 0; i < commits.nr; i++) {
916 int hash_pos;
917 struct pseudo_merge_commit_idx *c;
918
919 hash_pos = kh_get_oid_map(writer->pseudo_merge_commits,
920 commits.oid[i]);
921 if (hash_pos == kh_end(writer->pseudo_merge_commits))
922 BUG("could not find pseudo-merge commit %s",
923 oid_to_hex(&commits.oid[i]));
924
925 c = kh_value(writer->pseudo_merge_commits, hash_pos);
926 if (c->nr == 1)
927 continue;
928
929 hashwrite_be32(f, c->nr);
930 for (j = 0; j < c->nr; j++)
931 hashwrite_be64(f, pseudo_merge_ofs[c->pseudo_merge[j]]);
932 }
933
934 /* write positions for all pseudo merges */
935 for (i = 0; i < writer->pseudo_merges_nr; i++)
936 hashwrite_be64(f, pseudo_merge_ofs[i]);
937
938 hashwrite_be32(f, writer->pseudo_merges_nr);
939 hashwrite_be32(f, kh_size(writer->pseudo_merge_commits));
940 hashwrite_be64(f, table_start - start);
941 hashwrite_be64(f, hashfile_total(f) - start + sizeof(uint64_t));
942
943 for (i = 0; i < writer->pseudo_merges_nr; i++)
944 bitmap_free(commits_bitmap[i]);
945
946 oid_array_clear(&commits);
947 free(pseudo_merge_ofs);
948 free(commits_bitmap);
949}
950
951static int table_cmp(const void *_va, const void *_vb, void *_data)
952{
953 struct bitmap_writer *writer = _data;
954 struct bitmapped_commit *a = &writer->selected[*(uint32_t *)_va];
955 struct bitmapped_commit *b = &writer->selected[*(uint32_t *)_vb];
956
957 if (a->commit_pos < b->commit_pos)
958 return -1;
959 else if (a->commit_pos > b->commit_pos)
960 return 1;
961
962 return 0;
963}
964
965static void write_lookup_table(struct bitmap_writer *writer, struct hashfile *f,
966 off_t *offsets)
967{
968 uint32_t i;
969 uint32_t *table, *table_inv;
970
971 ALLOC_ARRAY(table, bitmap_writer_nr_selected_commits(writer));
972 ALLOC_ARRAY(table_inv, bitmap_writer_nr_selected_commits(writer));
973
974 for (i = 0; i < bitmap_writer_nr_selected_commits(writer); i++)
975 table[i] = i;
976
977 /*
978 * At the end of this sort table[j] = i means that the i'th
979 * bitmap corresponds to j'th bitmapped commit (among the selected
980 * commits) in lex order of OIDs.
981 */
982 QSORT_S(table, bitmap_writer_nr_selected_commits(writer), table_cmp, writer);
983
984 /* table_inv helps us discover that relationship (i'th bitmap
985 * to j'th commit by j = table_inv[i])
986 */
987 for (i = 0; i < bitmap_writer_nr_selected_commits(writer); i++)
988 table_inv[table[i]] = i;
989
990 trace2_region_enter("pack-bitmap-write", "writing_lookup_table", writer->repo);
991 for (i = 0; i < bitmap_writer_nr_selected_commits(writer); i++) {
992 struct bitmapped_commit *selected = &writer->selected[table[i]];
993 uint32_t xor_offset = selected->xor_offset;
994 uint32_t xor_row;
995
996 if (xor_offset) {
997 /*
998 * xor_index stores the index (in the bitmap entries)
999 * of the corresponding xor bitmap. But we need to convert
1000 * this index into lookup table's index. So, table_inv[xor_index]
1001 * gives us the index position w.r.t. the lookup table.
1002 *
1003 * If "k = table[i] - xor_offset" then the xor base is the k'th
1004 * bitmap. `table_inv[k]` gives us the position of that bitmap
1005 * in the lookup table.
1006 */
1007 uint32_t xor_index = table[i] - xor_offset;
1008 xor_row = table_inv[xor_index];
1009 } else {
1010 xor_row = 0xffffffff;
1011 }
1012
1013 hashwrite_be32(f, writer->selected[table[i]].commit_pos);
1014 hashwrite_be64(f, (uint64_t)offsets[table[i]]);
1015 hashwrite_be32(f, xor_row);
1016 }
1017 trace2_region_leave("pack-bitmap-write", "writing_lookup_table", writer->repo);
1018
1019 free(table);
1020 free(table_inv);
1021}
1022
1023static void write_hash_cache(struct hashfile *f,
1024 struct pack_idx_entry **index,
1025 uint32_t index_nr)
1026{
1027 uint32_t i;
1028
1029 for (i = 0; i < index_nr; ++i) {
1030 struct object_entry *entry = (struct object_entry *)index[i];
1031 hashwrite_be32(f, entry->hash);
1032 }
1033}
1034
1035void bitmap_writer_set_checksum(struct bitmap_writer *writer,
1036 const unsigned char *sha1)
1037{
1038 hashcpy(writer->pack_checksum, sha1, writer->repo->hash_algo);
1039}
1040
1041void bitmap_writer_finish(struct bitmap_writer *writer,
1042 struct pack_idx_entry **index,
1043 const char *filename,
1044 uint16_t options)
1045{
1046 static uint16_t default_version = 1;
1047 static uint16_t flags = BITMAP_OPT_FULL_DAG;
1048 struct strbuf tmp_file = STRBUF_INIT;
1049 struct hashfile *f;
1050 off_t *offsets = NULL;
1051 uint32_t i, base_objects;
1052
1053 struct bitmap_disk_header header;
1054
1055 int fd = odb_mkstemp(writer->repo->objects, &tmp_file,
1056 "pack/tmp_bitmap_XXXXXX");
1057
1058 if (writer->pseudo_merges_nr)
1059 options |= BITMAP_OPT_PSEUDO_MERGES;
1060
1061 f = hashfd(writer->repo->hash_algo, fd, tmp_file.buf);
1062
1063 memcpy(header.magic, BITMAP_IDX_SIGNATURE, sizeof(BITMAP_IDX_SIGNATURE));
1064 header.version = htons(default_version);
1065 header.options = htons(flags | options);
1066 header.entry_count = htonl(bitmap_writer_nr_selected_commits(writer));
1067 hashcpy(header.checksum, writer->pack_checksum, writer->repo->hash_algo);
1068
1069 hashwrite(f, &header, sizeof(header) - GIT_MAX_RAWSZ + writer->repo->hash_algo->rawsz);
1070 dump_bitmap(f, writer->commits);
1071 dump_bitmap(f, writer->trees);
1072 dump_bitmap(f, writer->blobs);
1073 dump_bitmap(f, writer->tags);
1074
1075 if (options & BITMAP_OPT_LOOKUP_TABLE)
1076 CALLOC_ARRAY(offsets, writer->to_pack->nr_objects);
1077
1078 if (writer->midx)
1079 base_objects = writer->midx->num_objects +
1080 writer->midx->num_objects_in_base;
1081 else
1082 base_objects = 0;
1083
1084 for (i = 0; i < bitmap_writer_nr_selected_commits(writer); i++) {
1085 struct bitmapped_commit *stored = &writer->selected[i];
1086 int commit_pos = oid_pos(&stored->commit->object.oid, index,
1087 writer->to_pack->nr_objects,
1088 oid_access);
1089
1090 if (commit_pos < 0)
1091 BUG("trying to write commit not in index");
1092 stored->commit_pos = commit_pos + base_objects;
1093 }
1094
1095 write_selected_commits_v1(writer, f, offsets);
1096
1097 if (options & BITMAP_OPT_PSEUDO_MERGES)
1098 write_pseudo_merges(writer, f);
1099
1100 if (options & BITMAP_OPT_LOOKUP_TABLE)
1101 write_lookup_table(writer, f, offsets);
1102
1103 if (options & BITMAP_OPT_HASH_CACHE)
1104 write_hash_cache(f, index, writer->to_pack->nr_objects);
1105
1106 finalize_hashfile(f, NULL, FSYNC_COMPONENT_PACK_METADATA,
1107 CSUM_HASH_IN_STREAM | CSUM_FSYNC | CSUM_CLOSE);
1108
1109 if (adjust_shared_perm(writer->repo, tmp_file.buf))
1110 die_errno("unable to make temporary bitmap file readable");
1111
1112 if (rename(tmp_file.buf, filename))
1113 die_errno("unable to rename temporary bitmap file to '%s'", filename);
1114
1115 strbuf_release(&tmp_file);
1116 free(offsets);
1117}